1. Effects of postural and visual stressors on myofascial trigger point development and motor unit rotation during computer work 
Jeffrey A. Hoyle, William S. Marras, James E. Sheedy, Dennis E. Hart 
Journal of Electromyography and Kinesiology 
Volume 21, Issue 1, Pages (February 2011)
DOI: /j.jelekin
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2. Fig. 1
Depiction of three experimental conditions (from left to right, VL/PL, VH/PL, VL/PH).
Journal of Electromyography and Kinesiology  , 41-48DOI: ( /j.jelekin )
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3. Fig. 2
Placement of surface electrode array (14 channels) over trapezius muscle. Channel 7 records EMG data directly over the trigger point location, as determined by myofascial specialist.
Journal of Electromyography and Kinesiology  , 41-48DOI: ( /j.jelekin )
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4. Fig. 3
EMG analysis and FFT processing illustration to calculate the running means of the median frequencies. FFT=Fast Fourier Transform.
Journal of Electromyography and Kinesiology  , 41-48DOI: ( /j.jelekin )
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5. Fig. 4
Average median frequency cycles (across all spatial locations combined) as a function of condition. Whiskers=1 standard deviation. Results showed that all three conditions were significantly different from one another.
Journal of Electromyography and Kinesiology  , 41-48DOI: ( /j.jelekin )
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6. Fig. 5
Average median frequency cycles (across all subjects) as a function of muscle spatial location (relative to MTrP). Location highlighted in red represents the MTrP location. Green (lighter) locations represent locations that are significantly different from MTrP location (p<0.05). Grey discs indicate electrode placement while the dotted lines represent muscle striation lines.
Journal of Electromyography and Kinesiology  , 41-48DOI: ( /j.jelekin )
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7. Fig. 6
Mean VAS scores for neck/backache (post–pre) as a function of condition. Whiskers=1 standard deviation. Results showed that VL/PL and VL/PH conditions were significantly different; however, VH/PL condition was not significantly different from the other two conditions.
Journal of Electromyography and Kinesiology  , 41-48DOI: ( /j.jelekin )
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